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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

45784 results found.

  1. GRB 240824A: GIT optical upper limit
  2. GRB 240819A: Swift afterglow confirmation
  3. GRB 240825A: TNG optical photometry and spectroscopy
  4. LIGO/Virgo/KAGRA S240825ar: Updated Sky localization
  5. LIGO/Virgo/KAGRA S240825ar: Updated Sky localization
  6. GRB 240825A: NUTTelA-TAO / BSTI Optical Limits
  7. GRB 240825A: GMG Continued Optical Observation on the Second Night
  8. GRB 240824B: Ondrejov D50 optical limit
  9. GRB 240825A: KAIT optical observations
  10. GRB 240825A: PRIME near-infrared detection
  11. Konus-Wind detection of GRB 240825A (bright/long)
  12. GRB 240825A: Fermi GBM Observation
  13. GRB 240825A : MISTRAL/T193 OHP optical follow-up of the afterglow
  14. GRB 240825A: AKO Optical Follow-Up Observations
  15. GRB 240825A: AstroSat CZTI detection of the long bright burst
  16. SGR 1E 1841-045 / Kes 73: SVOM/GRM observation
  17. GRB 240825A: Swift/UVOT Detection
  18. GRB 240825A: REM detection of the optical/NIR afterglow
  19. GRB 240825A: Swift-XRT refined Analysis
  20. GRB 240825A: VLT/X-shooter redshift
  21. GRB 240825A: SVOM/C-GFT optical observations
  22. GRB 240825A: Montarrenti Observatory optical observations
  23. GRB 240825A: Enhanced Swift-XRT position
  24. GRB 240825A: MASTER optical counterpart observation
  25. GRB 240825A: Fermi-LAT detection
  26. GRB 240825A: LCO optical observations
  27. GRB 240824B: KAIT optical upper limit
  28. SGR 1E 1841-045 / Kes 73 (Trigger 1249878): Osservatorio Atronomico Nastro Verde optical upper limit
  29. GRB 240824B: Fermi GBM Observation
  30. Fermi GRB 240825A: Global MASTER-Net observations report
  31. SGR 1E 1841-045 / Kes 73 (Trigger 1249653) - Osservatorio Astronomico Nastro Verde upper limit
  32. GRB 240824B: NOT optical upper limit
  33. GRB 240825A: GMG Optical Observation
  34. Swift GRB 240825A: Global MASTER-Net observations report
  35. GRB 240825A: 1.6m Mephisto multi-band detection
  36. GRB 240825A: AKO Optical Afterglow Detection
  37. GRB 240825A: Skynet Optical Afterglow observations
  38. GRB 240825A: Nanshan/HMT optical afterglow observations
  39. GRB 240825A: Swift detection of a burst with a bright optical counterpart
  40. GRB 240825A: Fermi GBM Final Real-time Localization
  41. GRB 240824A: Swift-BAT refined analysis
  42. GRB 240824A: SVOM/C-GFT optical upper limit
  43. GRB 240824B: Swift-XRT afterglow detection
  44. GRB 240824A: Swift-XRT observations
  45. LIGO/Virgo/KAGRA S240825ar: Identification of a GW compact binary merger candidate
  46. GRB 240824B: Swift/BAT arcminute localization of a burst
  47. GRB 240824B: Swift ToO observations
  48. Fermi GRB 240824C: Global MASTER-Net observations report
  49. GRB 240824C: Fermi GBM Final Localization
  50. GRB 240824A: Swift/UVOT Upper Limits
  51. GRB 240821A: Swift/UVOT observations of the XRT sources.
  52. GRB 240824B: MAXI/GSC detection
  53. GRB 240824B: Fermi GBM Final Real-time Localization
  54. GRB 240824A: Retraction of GCN 37255
  55. GRB240824A: GRANDMA/TAROT-TCA Upper Limit
  56. SGR 1E 1841-045 / Kes 73: Leavitt Observatory optical upper limit
  57. GRB 240824A: KAIT optical upper limit
  58. GRB 240824A: Skynet Optical Afterglow Discovery
  59. GRB 240824A: Swift detection of a burst
  60. Swift GRB240824.04: Global MASTER-Net observations report
  61. SGR 1E 1841-045 / Kes 73: Montarrenti Observatory optical upper limits
  62. GRB 240821A: Colibri Optical Upper Limit
  63. EP240820a: PRIME J-band Observations
  64. GRB 240821A: Swift-XRT observations
  65. GRB 240822A: AstroSat CZTI detection of a short burst
  66. GRB 240821A: REM optical/NIR upper limits
  67. GRB 240821A: LCO optical observations
  68. GRB 240821A: JinShan optical upper limits
  69. GRB 240809A: Mondy and AbAO Optical Observations
  70. GRB 240821A: SVOM/VT follow-up and optical upper limit
  71. GRB 240821A: GMG Optical Upper Limit
  72. Fermi GRB 240821A: Global MASTER-Net observations report
  73. GECAM-B observation of a short burst from SGR 1E 1841-045 / Kes 73
  74. GRB 240821A: Fermi GBM Observation
  75. Fermi trigger No 745964969: Global MASTER-Net observations report
  76. Fermi trigger No 745925274: Global MASTER-Net observations report
  77. GRB 240821A: Swift ToO observations
  78. Fermi trigger No 746019401: Global MASTER-Net observations report
  79. Fermi-GBM Observations of the reactivation of SGR 1E 1841-045 / Kes 73
  80. Fermi trigger No 745935375: Global MASTER-Net observations report
  81. GRB240821A: EIRSAT-1 GMOD Detection
  82. GRB240821B: First GRB Detected by EIRSAT-1 GMOD
  83. GRB 240821A: EP-FXT follow-up observation and afterglow candidates
  84. Fermi GRB 240821B: Global MASTER-Net observations report
  85. EP240801a: Keck/LRIS spectroscopic redshift confirmation
  86. GRB 240821A: SVOM/GRM observation
  87. GRB 240821A: SVOM/GRM observation
  88. GRB 240821A: GRANDMA/LesMakes-T60 Upper Limit
  89. GRB 240821B: Fermi GBM Final Localization
  90. Fermi trigger No 745866488: Global MASTER-Net observations report
  91. Trigger 1249878: Swift detection of another burst from SGR 1E 1841-045 / Kes 73
  92. GRB 240821A: BALROG localization (Fermi Trigger 745958167 / GRB 240821775)
  93. GRB 240821A : a likely short GRB detected by SVOM/ECLAIRs
  94. GRB 240821A: Fermi GBM Final Real-time Localization
  95. GRB 240819A: Swift-XRT observations
  96. GRB 240819A: JinShan optical upper limits on one Swift/XRT source
  97. GRB 240820B: SVOM/GRM observation
  98. EP240820a: TRT optical upper limit
  99. EP240820a: EP detection of a fast X-ray transient
  100. GRB 240819A: KAIT optical upper limit

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